We're happy to announce that the Exchange Server Deployment Assistant has been enhanced to include support for configuring rich coexistence for organizations interested in maintaining some users on-premises with Exchange 2007 and some users hosted by Microsoft Office 365 Beta for enterprises in the cloud. This scenario is in addition to the existing support for configuring rich coexistence between on-premises Exchange 2003 organizations and Office 365 Beta. The coexistence information is only available in English at this time and additional rich coexistence support for Exchange 2010 will be added the Deployment Assistant soon.

Rich coexistence (“hybrid deployment”) offers organizations the ability to extend the feature-rich experience and administrative control they have with their existing on-premises Microsoft Exchange organization to the cloud. It provides the seamless look and feel of a single Exchange organization between an on-premises organization and a cloud-based organization. In addition, coexistence can serve as an intermediate step to moving completely to a cloud-based Exchange organization. This approach is different than the simple exchange migration ("cutover migration") and staged Exchange migration options currently offered by Office 365 Beta outlined in E-Mail Migration Overview.

If you are not already familiar with the Deployment Assistant, it allows you to create Exchange Server 2010 on-premises configuration and deployment instructions that are customized to your environment. It asks you a small set of simple questions and it provides a checklist with instructions that are designed to deploy or configure Exchange 2010 based on your answers. In addition to the online checklist, you can even print a PDF of your checklist.

Your feedback is very important for the continued improvement of the Deployment Assistant. We would love your feedback on this new scenario and any other area of the Deployment Assistant. Feel free to either post comments on this blog post, provide feedback in the Office 365 community migration and coexistence forum, or email us at edafdbk@microsoft.com via the 'Feedback' link located in the header of every page of the Deployment Assistant.

Thanks Oscar. If by the '2010 assistant' you mean when is the scenario for configuration rich coexistence with Exchange 2010 on-premises and Microsoft Office 365 for enterprises going to release, we are targetting that as our next scenario that should release to the Exchange 2010 Deployment Assistant in the next couple of months.